cloud_aws: Corrected EIP assignment for non-vpc hosts.
cloud_aws: Add snapshot and poweron/poweroff operations

Simple snapshot creation, deletion, and reverting
for the root file systems of AWS EC2 VMs. Also powering
on and off of VMs (start/stop) now supported.
optimization: bucket items are stored in sets

Old implementation added same items multiple times to buckets
when the same poni tool object context was reused for multiple
operations.
readme: update dependencies.
added: poni control --ignore-missing

"poni control" operation does not fail when --ignore-missing
is specified and no matching operations are found.
Support for Eucalyptus cloud target
rcontrol_paramiko: send noop packets every 10 seconds

This makes sure that the connection is up and running and also makes sure
that firewalls or other gateway's don't timeout our SSH connections.
tool: convert "-d REPO" path to absolute path

Not all commands (e.g. "audit") fully worked with relative
repository paths.
poni: keyword to get script path and more information in file not found situation

Added a way to expand the directory from which a script was ran inside itself.
This is now possible with "$script_path" variable which will be rendered to a value
which is full path to the script with script filename removed.

Also added more verbosity when file is not found in update-config
cloud_libvirt: default to diskcache=none

"none" gives the best performance and reliability by default.  It also
allows VMs to be live-migrated across different hosts.  "writeback" is
faster in some workloads, but does not support live migration and may
not be as reliable in all situations.
rcontrol_paramiko: retry channel opening on failure

Retries "SSHException: Unable to open channel." failures in the
connecting phase in case transport or channel opening fails.
cloud: terminate all instances at a single provider in one call
cloud_libvirt: handle storage volume overwrite with libvirt 1.0 and newer

libvirt 1.0 changed the error string returned when a storage volume with
the requested name already exists; recognize both variants.
Merge remote-tracking branch 'f-secure/poni_fsc_contributions'
Merge remote-tracking branch 'f-secure/poni_eucalyptus_provider'
Merge remote-tracking branch 'saaros/libvirt_vol_overwrite'